#include <bits/stdc++.h>

using namespace std;

class Solution
{
public:
    int uniquePathsWithObstacles(vector<vector<int>> &obstacleGrid)
    {
        int m = obstacleGrid.size();
        int n = obstacleGrid[0].size();
        if (obstacleGrid[0][0] == 1 || obstacleGrid[m - 1][n - 1] == 1)
        {
            return 0;
        }
        vector<vector<int>> dp(m, vector<int>(n, 1));
        for (int i = 1; i < m; i++)
        {
            if (obstacleGrid[i][0] == 1)
            {
                dp[i][0] = 0;
                continue;
            }
            dp[i][0] = dp[i - 1][0];
        }
        for (int j = 1; j < n; j++)
        {
            if (obstacleGrid[0][j] == 1)
            {
                dp[0][j] = 0;
                continue;
            }
            dp[0][j] = dp[0][j - 1];
        }
        for (int i = 1; i < m; i++)
        {
            for (int j = 1; j < n; j++)
            {
                if (obstacleGrid[i][j] == 1)
                {
                    dp[i][j] = 0;
                    continue;
                }
                dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
            }
        }
        return dp[m - 1][n - 1];
    }
};

int main()
{
    vector<vector<int>> obstacleGrid{{0, 0, 0},
                                     {0, 1, 0},
                                     {0, 0, 0}};
    Solution sol;
    cout << sol.uniquePathsWithObstacles(obstacleGrid) << endl;
    return 0;
}